1. Field of the Invention
The present invention relates to a developing apparatus and the method of developing an electrostatic image using a single-component magnetic developer.
2. Description of the Prior Art
In the past, a magnetic brush developing method has generally been used as a developing system for a magnetic developer. This system has drawbacks that the developer may adhere to the non-image area and an image tends to become fogged due to the fact that magnetic developer has electric charges dispersed with positive and negative polarities owing to internal frictional electrification, and due to further frictional electrification caused by the contact of said developer with the electrostatic image holder etc.
Furthermore, there are drawbacks in that said developer coheres on the developing member and thereby the ability to be conveyed thereon is remarkably lowered. The primary reasons for this are considered to be that the thickness of a layer of developer on the developing member needs to be kept thin for a magnetic developer, and cohesion takes place under stress caused by the thickness-regulating plate for the developer resulting in less fluidity, and cohesion takes place under the stress of that developer located between the electrostatic image holder and the developing member.